In order to observe the exprssion of SP and ALP in rat pulp after direct pulp capping by low level laser +Dycal, 64 SD rats were randomly divided into 4 groups (n=16):Normal control group (ZC group), low level laser group (LLL group), Dycal group (Dy group) and low level laser+Dycal group (LLL+Dy group). The first molars of the left maxillary and mandibular of the rats mechanical wear pulp after direct pulp capping. SP and ALP expression in pulp tisssue was measured with immunohistochemical staining in different time. The mean optical density (MOD) of each specimen was measured. The results show that: According to the statistical analysis of two-factor univariate variance, there was a significant difference in SP expression on the 7th and 14th day after surgery. SP expression reached its peak and LLL+Dy group>Dy gruop>LLL group>ZC group(P<0.05) on the 14th day. ALP expression reached its peak and LLL+Dy group>LLL group>Dy group>ZC group (P<0.05) on the 7th day. SP and ALP expression gradually decreased to normal level with the formation of repaired dentin on the 28th day. Conclusion: The low level laser and Dycal can promote the repair of pulp injury and the formation of restorative dentin, which may be related toinduction of the expression of SP and ALP.